Dead battery... again

[jms02050]

Hi. In August my 6yr old 8D house battery, which had been in service this season since May, appeared to no longer hold a charge - so a new 8D went in b/c i though it was an age issue. Down to the boat today and I couldn't even power up the DC panel with the shiny new 8D. So it appear that it took about 3-4 months of use to kill an 8D with light use as a house battery.

I'm thinking maybe the charger isn't charging my house battery, only the starting battery. I've read many threads on the topic, and I know I've got some sleuthing to do, but would love to know if there are any obvious places to start. Worth noting that I leave my switch in the off position when on running the Protech 4 Series charger when I'm at the dock.

Thanks in advance.

[RobS]

Start by putting a VM across the terminals and check that it is getting charge.

[N4QC]

Based on the owner's manual for the Protech 4 - "The unit should be permanently
mounted in your boat and wired directly to your batteries.
Three isolated outputs are incorporated to sense and
charge three separate heavy-duty batteries or battery
banks as needed.", I recommend that you verify the wiring from the charger to each of the batteries.

Also, confirm that the appropriate battery type is selected at the charger for each branch.

Is the switch that is turned off at the dock the switch that feeds AC to the charger?

Hope this helps,

[jcollins]

I have a Prosine in my boat. I may be wired wrong but if I turn the switch off it does not charge.
On 1 - Just the house
On 2 - Just starting batteries.
All - all 3 charge.

Then again the admiral says I'm not wired right.

[craw_daddy]

On Grace Full, my battery selector switch must be in the 'both' position for both batteries to charge from the on-board charger.

When I leave her I have the battery switch set to both, but the 12V panel main switch to off & the 120VAC panel on and battery charger on.

[jms02050]

Hmmm. I tested for incoming voltage when turning on the charger, but I had the battery switch in the OFF position. I'll take another look.

[RobS]

Did you test it with the engine running?

What position do you leave you battery switch in when running? If you never switch to ALL or House your engine is likely never charging your battery while underway. So if your 110V charger isn't charging it AND your engine is never charging it.........

[jms02050]

Haven't tested with the engine running yet. Was just at the boat - the charger powers up and sends juice to the starting battery regardless of battery switch position. There are 2 red wires coming off the charger - I was thinking one might be bad so I tried swapping them from starting to house battery but no change. The house still isn't getting a charge per my VM. This is a head scratcher.

[craw_daddy]

If your vessel is liek mine, it is wired with two hot wires coming off your charger -one running to each battery. But I think you will find that there is only one negative wire that comes from the charger which feeds the larger battery. IYour 2nd battery will have two posotive wires and one negative wire attached to it.

In order to get the other battery to charge (regardless of vessel battery switch position) you will likely need to run a 2nd negative wire from the charger to the other battery. I believe it should be ~8 guage wire. Or you could leave the battery selector switch to both, which will provide a closed path for your charger to charge the smaller battery.

[jms02050]

Oh boy. After reading Craw_Daddy's post and looking at a couple of pics, I'm thinking that the hot and ground from the charger are mounted to the positive terminal on my house battery. This is how the previous owner had her rigged....

See the pics below.

I'm assuming the wire marked with the arrow is the ground wire coming off the charger.

charger.jpg

And here's my problematic house battery. Note that I've got a hot and ground from the charger going to the hot terminal.

batteries.jpg

[jms02050]

And here's the result... the hot wire from the charger is fried.

IMG_1010.jpg

[RobS]

Yes, the yellow wire going to the fuse block is the NEG protection against reverse polarity. In your last photo there are 3 POS lugs, 2 are jumpered together since you have 2 batteries, not 3. Are the 2 POS leads going to the 2 different batteries?

[jms02050]

Yes Rob. The charger is set up for only 2 batteries. Each positive wire goes to a battery. The wire that's fried was attached to the battery that also had the charger's ground wire on the positive post. The battery, new in August, read 1.4 volts. We'll see if I can bring it back...

[RobS]

...The battery, new in August, read 1.4 volts. We'll see if I can bring it back...

When you say "bring it back", you mean bring it back to the store, right?

If you give it a shot, be sure to charge it as sloooooow as possible right from the start, don't fast charge it and then let it trickle. Use a charger other than your on-board charger.

[jms02050]

Yeah, I know, wishful thinking. On the bright side, I got past my mental block and figured out how my charger is set up. Should be fun seeing if I fried my charger as well. Yup... ending the season like the local weather here in eastern Mass... with a thud.